Synthesis of TiO<sub>2</sub>-Modified Hydroxyapatite with Various Morphology by Urea-Assisted Hydrothermal Method

In this study, we synthesized the TiO 2 -modified hydroxyapatite (HAp) with various morphologies by hydrothermal treatment using urea decomposition, at 160 oC for 6 h. After hydrothermal treatment, carbonate-substituted HAp and TiO 2 (anatase) phases were formed in products using 1.0-0.1 M urea solution. The morphology of synthesized HAp changed from small plate-shaped to long needle-shaped crystals with decreasing the urea concentration. The photocatalytic property for samples was investigated by decoloration test using 25 ppm methylene blue solution. In comparison with HAp samples without TiO 2 , the TiO 2 -modified HAp clearly showed the photocatalytic decomposition of methylene blue by UV irradiation.